Gotta agree with cadrina. Dinosaurs were killed by the explosion of a time-traveling freighter that had been full of Cybermen. And Adric was there. As far as I'm concerned there's no further debate necessary.
lol. I love that first pic with the dino keeled over on it's back with the green vomit. Ah, just like how I originally imagined the dinosaurs died... in a pool of their own vomit.
I dunno, maybe I'm thick, but it sounds like the article describes a series of asteroid impacts over a 300,000 year span. That kind of repeated pounding from asteroids/comets is hardly proof that asteroids/comets did not wipe out the dinos, only proof that it wasn't a single impact snuffing the bigguns, and that was already pretty well established by (sorry) Robert Bakker, who notes the many species that survived long after Chicxulub. He proposes that volcanism, migratatory behaviors (spreading dino-plagues) and other stresses all took their toll. But personally, I like the Predator idea. Crab-faced alien hunters did the job, yepyep.
@Aethelred: I can't claim expertise on the subject, but reading the articles a few times through seemed to say that part of it was that so many impacts suggest they aren't nearly as destructive as we've previously thought. It's just a geological coincidence that they happened around the same time as the volcanoes, which are far more powerful and destructive and thus the real engine of extinction.
@Alasdair Wilkins: And by "I think", I of course mean "I think that's what the article said." When I saw it posted it just seemed to come across as more of a philosophical statement.
Okay. Dinosaur extinction (not that they did go extinct. Birds and all, what?) has officially become the scientific equivalent of whether milk is bad for you. Every couple of years, they turn it around.
As I have said repeatedly, the asteroid impact was only one of many causative factors that led to the collapse of the dinosaurs. The asteroid didn't simply kill all dinosaurs instantly, but I feel like it set off a chain reaction of events (which no doubt included volcanic activity and seismic disturbances) that led, ultimately, to the chain of dinosaur life being broken. If the impact caused enough collateral damage, then the food chain at the time would have collapsed, perhaps not all at once, but very rapidly. Plant-eaters would have been hardest hit, as meat eaters would have been able to scavenge for long periods of time. Eventually, once enough of the plant-eaters died off, the meat-eaters would have followed suit.
@NefariousNewt: Ah, I didnt know you had credentials as an archaeologist. Also if it set off a chain of events, why did it take 300,000 years? If the impact didnt wipe out a single species, then how could it hit hard enough to cause "a chain of events" that lead to worldwide dino extinction?
@NefariousNewt: You've obviously been affected by the Pro Asteroid lobby.
I prefer to think the reason is more related to the gradual loss of oxygen on the planet. Animals over a certain mass need exponential amounts of oxygen to survive. As the atmosphere thinned, larger animals would have gotten smaller to compensate.
I realize I have nothing to back this up, and instead would like to posit that they were killed by disease.
@NefariousNewt: I'm not so sure carnivores could scavenge "for long periods of time". How long does dead meat last? Weeks, maybe. Certainly not months. And I'm pretty sure they didn't have a lot of freezers handy.
Herbivores, on the other hand, will often substitute a less preferred plant for their usual fare when forced to do so.
@Multibocks: @AngryEddy: @NerD!!!: Well, scoff if you like, but it doesn't require an archaeology degree to apply some physics and some logic to the situation. Any asteroid impact that would have killed all the dinosaurs would have had to be on such a scale that most life on Earth could not have survived. We certainly wouldn't be here arguing about it only 65 million years after the fact. Plus, to kill all the dinosaurs, would have required impacts globally, not one impact in one spot.
As we've seen from the eruptions of volcanoes like Mount Pinatubo and Krakatoa, while large amounts of ash can be dumped into the air and cause major shifts in light levels and temperature, the suspended particulates do not remain indefinitely, and the turbulence of the atmosphere would certainly wash out the particulates on a fairly short timespan, say less than 10 years. Damage would definitely done, though I think it's safe to say that given the violence of the blow, a great deal of material might have been ejected into space. It's hard to say how much material would have stayed in the atmosphere, and what kind of coverage it would generate. Certainly not all plant or animal life would have died.
There would have been a fairly fast die-off of the larger plant-eating dinosaurs, as they required tons of vegetation daily to survive. Smaller dinosaurs would have survived on the remaining vegetation, though that too would slowly disappear to the extent that it would not support the remaining plant-eaters. Meat-eaters would thrive on the carrion, but eventually even those sources would dry up, and they would end up turning on themselves. Disease would run rampant. All the while, out tiny ancestors would be riding this out.
And yes, this would take time. 300,000 is not inconceivable. You've got to remember that natural selection is at work as well, so some species are better equipped to adapt to the sudden changes in conditions.
@Counterglow: Sure they could, if the die-off of herbivores is slow and steady. True, supplies would be spotty, especially after the large, slow herbivorous dinosaurs died and the remaining, more agile ones were all that was left. All dinosaur populations would fall, inevitably.
@NefariousNewt: Well, scoff if you like, but it doesn't require an archaeology degree to apply some physics and some logic to the situation.
The problem is that without years spent learning about a field of study, you have no clue whether or not what you're applying is actually logic. And to be honest, it really doesn't sound like you know much about anything here. 300 000 years for an entire biosphere to die out with the assumption that a majority of plants are largely wiped out in a matter of a few years? That's just silly.
05/07/09
I killed the dinosaurs, dammit!
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Changing the course of evolution is tricky, even for aliens.
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He proposes that volcanism, migratatory behaviors (spreading dino-plagues) and other stresses all took their toll.
But personally, I like the Predator idea. Crab-faced alien hunters did the job, yepyep.
05/06/09
I think.
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What is it now? Bad or good? I might have to empty out my fridge!
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Ah, I didnt know you had credentials as an archaeologist. Also if it set off a chain of events, why did it take 300,000 years? If the impact didnt wipe out a single species, then how could it hit hard enough to cause "a chain of events" that lead to worldwide dino extinction?
05/06/09
I prefer to think the reason is more related to the gradual loss of oxygen on the planet. Animals over a certain mass need exponential amounts of oxygen to survive. As the atmosphere thinned, larger animals would have gotten smaller to compensate.
I realize I have nothing to back this up, and instead would like to posit that they were killed by disease.
05/06/09
Herbivores, on the other hand, will often substitute a less preferred plant for their usual fare when forced to do so.
05/06/09
As we've seen from the eruptions of volcanoes like Mount Pinatubo and Krakatoa, while large amounts of ash can be dumped into the air and cause major shifts in light levels and temperature, the suspended particulates do not remain indefinitely, and the turbulence of the atmosphere would certainly wash out the particulates on a fairly short timespan, say less than 10 years. Damage would definitely done, though I think it's safe to say that given the violence of the blow, a great deal of material might have been ejected into space. It's hard to say how much material would have stayed in the atmosphere, and what kind of coverage it would generate. Certainly not all plant or animal life would have died.
There would have been a fairly fast die-off of the larger plant-eating dinosaurs, as they required tons of vegetation daily to survive. Smaller dinosaurs would have survived on the remaining vegetation, though that too would slowly disappear to the extent that it would not support the remaining plant-eaters. Meat-eaters would thrive on the carrion, but eventually even those sources would dry up, and they would end up turning on themselves. Disease would run rampant. All the while, out tiny ancestors would be riding this out.
And yes, this would take time. 300,000 is not inconceivable. You've got to remember that natural selection is at work as well, so some species are better equipped to adapt to the sudden changes in conditions.
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The problem is that without years spent learning about a field of study, you have no clue whether or not what you're applying is actually logic. And to be honest, it really doesn't sound like you know much about anything here. 300 000 years for an entire biosphere to die out with the assumption that a majority of plants are largely wiped out in a matter of a few years? That's just silly.
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